28 銘柄のパフォーマンスランキング

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations are provided, but the description discloses important behaviors: the tool only sorts numbers without investment advice, and it has a limitation on periods (1w/1m only support 7 assets). This effectively communicates the tool's non-destructive, read-only nature.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Two concise sentences: the first explains the core functionality, the second adds important limitations and disclaimer. No superfluous words.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a tool with 2 parameters and no output schema, the description explains the scope, limitation, and non-advisory nature. It could be more explicit about the performance metric (e.g., percent change), but the schema's period descriptions partially cover that. Overall, it is complete enough for typical use.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Both parameters are fully described in the schema (100% coverage). The description adds the context that topN returns both top and bottom, but this is already implied by '上位 N と下位 N'. So the description adds minimal value beyond the schema.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states it sorts 28 assets by performance over a specified period and returns top and bottom N. It specifies the covered asset classes (forex, stocks, rates, commodities, crypto) and distinguishes itself from sibling tools which deal with calculations, quotes, etc.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides clear context: for 1w/1m periods only 7 main assets are supported, and it explicitly states it is not an investment recommendation. However, it does not directly compare to alternative tools or specify when not to use it.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.